The present invention relates to auger machines and, more particularly, to auger machines having large auger screws cantilevered within a grinding chamber and supported by a bearing assembly mounted on a bulkhead.
With certain types of grinding and shredding machines, also known as auger shredders, it is desirable to mount the shredding element, which may be a tapered screw, within a grinding chamber of the machine so that it is cantilevered from a wall or bulkhead to extend substantially horizontally within the grinding chamber. An example of such a device is shown in Koenig U.S. Pat. No. 4,253,615, which shows a single auger screw mounted within a grinding chamber. Koenig U.S. Pat. No. 4,938,926 shows an auger shredder having two opposing screws, positioned side by side, within a grinding chamber. With the latter patent, the screws are mounted on opposing bulkheads.
In each device, the auger screw is mounted on the drive shaft of a rotary hydraulic motor and is supported by the inner race of a bearing whose outer race is mounted on the outboard face of the bulkhead. An example of such structure is shown in Koenig U.S. Pat. No. 4,951,884. That patent shows an auger shredder having an auger screw mounted on a bearing disk and a motor drive shoe. The bearing disk is attached to the inner or rotational race of the main bearing, while the outer or stationary race is attached to a mounting ring which, in turn, is attached to a cylindrical extension from the outboard face of the bulkhead.
In order to remove the bearing in such a device for maintenance or repair, it is necessary for workers to enter the grinding chamber to remove such components as a bearing shield, which may be a segmented ring mounted on the bearing disk which overlaps and fits within an annular rabbet machined into the inboard face of the bulkhead to form a labyrinth between the rotating bearing disk and non-rotating bulkhead. Within the outer bearing shield is an inner bearing shield, also a segmented ring, which is mounted on the bulkhead and also must be removed to effect removal of the bearing assembly.
Accordingly, there is a need for a bearing design which enables removal of the auger screw, bearing and drive motor from the outboard side of the bulkhead, thereby eliminating the need for entry into the grinding chamber.